Draft controlling device



Nov. l5, 1949 H. M. CUNNINGHAM 2,437,856

DRAFT CQNTROLLING DEVICE Filed Feb. s, 194e l/vvE/vroR. Hal Munnjngham.

Bx APR 191949 MJW.

A TTORNE Y Patented Nov. 15, 1949 @UNITED STATES PATENT oI-Flcls Hal M. Cunningham, Branford, Conn. Application FebruarycS, 1946, Serial No. 646,398

6 Claims.

This invention relates to improvements in draft controlling devices and more particularly to improvements in automatic draft controls of the form shown in Patent No. 2,251,440 issued August 5, 1941, and entitled Furnace flue damper. In draft control devices of the above nature it is particularly desirable that the face of the draft control plate of the device be disposed in a vertical plane and that the frame holding this plate be snugly engaged against the open end of the flue extension to prevent rocking movement. It is also particularly desirable that the frame and ue extension be firmly secured together to prevent them separating should sudden pressure be developed in the iiue. It is also desirable that the connection between the frame and the fiue extension be conveniently and readily connected and disconnected to permit eflicient attachment of the device to existing installations, and to allow adjustments, of the device in respect to the flue extension to be conveniently and quickly made.

The objects of this invention are: to provide means in a draft controlling device of the above nature to insure proper location assembly of the device to a flue extension; to provide eicient means to connect the frame of the device to the flue extension which can be readily and conven iently actuated; and to provide an improved form of holding frame for the operating damper plate of the device whereby the device locating means and the frame connecting means are efficiently and conveniently associated with other structural features of the device.

A further object of this invention is to provide an improved draft control device which will be relatively inexpensive to manufacture, simple in construction, pleasing in appearance, compact, and very efficient and durable in use.

With these and other objects ine-view, which will appear as the description proceeds, there hasV been illustrated in the accompanying drawings a form in which the features and principles of Vthis invention may be conveniently and practically embodied. l

In the drawings:

Figure 1 is a front view of a portion of a flue pipe having a flue extension attached thereto and shows an edge view of a draft control deviceembodying the features and principles of this invention secured to the open end of the flue extension; y

Figure 2 is an enlarged inside face View of the draft control device of this invention and is a` sectional view taken on the line 2-'-2 of Figure 1;

Figure 3 is an enlarged sectional view of the device taken on line 3-3 of Figure 2;

Figure 4 is a still further enlarged broken sectional view of the frame and flue extension connecting means; and f A f Y Figure 5 is an enlarged broken sectional view of the frame and flue extension locating means taken on line 5-5 of Figure 2.

Referring now to the drawings wherein like reference numerals designate like parts throughout the several views, the reference numeral II denotes a section of a flue pipe which connects a combustion chamber (not shown) with a chimney or stack (not shown) to carry away burned gasesand in which there is a continuous draft of constantly varying degrees of intensity. As specifically pointed out in 2,251,440, the draft control device comprises a frame I2 adapted to be secured to a flue extension I3 which in turn is attached to the flue pipe Il over a suitably formed opening (not shown) provided inthe flue pipe II in any convenient section thereof between the combustion chamber and the stack.

AY plate I4 ispivoted to the frame I2 to substantially cover a central opening therein when inA Vclosed position, it being urged into such closed position by an adjustable weight I5. A fiat leaf spring I6 is secured to the frame I2 and extends overthe rear face of the draft controlling plate into position to be engaged by the weight I5 to limit its opening movement of the plate I4. A pocket I'I is provided in the frame I2 in communication with the atmosphere outside of the iiue pipe I I and is positioned to be covered by the plate I4 when the latteris in closed position. v The pocket I'I is an essential element of the draft control device and its function is particularly pointed A out in the above referred to patent;

The improved frame I2 of this invention isl preferably cast, or otherwise formed, in one piece and comprises an annular flat rim portion I8 having a central opening I9, an annular flange `2l extending rearwardly from the front face of the rim portion I8 about the periphery of the opening I9,Vand an annularflange 22 extending,

rearwardly from the front face of the trim portion I8 about the outer periphery thereof. The.

rim portion I8 with the spaced apart flanges 2| and 22 forms a frame substantially U-shaped in cross-section wherebycthe same will be of substantial strength and the possibility of it warpingrwill be eliminated. A portion of the ange 2I ,forms one wall ofthe pocket I'I. A rear face wall 23 extends from the flange 2l toward theV the above referred to Patentcenter of the frame I2 and a wall 24 extends from the rear face wall 23 of the pocket outwardly to adjacent the plane of the front face of the rim portion I8.

The ange 2| extends rearwardly a greater amount than does the fiange 22 and is of the proper dimensions to snugly enter the open outer end 25 of the flue extension I3. To properly locate the frame I2 squarely against the end of the flue extensionA I3and to strengthen by crossbracing the flanges 2| and 22, a plurality of filler pieces 26, 21, 28, and 29 are peripherally spaced apart about the rim portion I 8 between the flanges 2| and 22. The rear faces 3-Iof the aforesaid ller pieces are aligned in the same plane, which is parallel to the front face of the rim I8, so that the end edgeof the ue extension I3 will seat against all of the said rear faces 3| and locate the frame I2 in proper position thereon.

The: filler pieces 26 and 218/ areI disposed diametrically opposite: eachother and each have a threaded holeV 32 for-med therein tol receive` a threaded bearing member. 33. The inner ends of the bearing members 33 have a pivotstud` 34 formed thereonv adapted to be recived into-a hole formed in= the end of ai rod 35- secured to the. plate I4 thereby for-ming: a' pivotal support for the plate I4.

The peripherallyf spaced. apart filler pieces- 27|y and 29 have lugsl36 andy3-1 extending rearwardly respectively therefrom. The lugs 36 and 31 are spaced outwardly from the ange 2| to permit the edgev ofA the end 25 of. theue. extension I3 passing therebetween to seat upon the ller pieces 21 and 29.V A threaded hole is provided in each of the lugs364 and 31- toreceiveathreaded clamp member 38 Which when screwed inwardlytoward the flue extension I3 clamps it firmly against the outer surface of the flange 2.-I-. If desired, the clamp member 384 is provided. with a rounded end 39 to inset into the material.V of. the flue extension. I3. or, as shown,the flange 2|-y may be countersunk as at 4I oppositethe rounded end 39 of the member. 3&Whereby, upon clamping the flue extension, its. material at this point will be depressed into the countersink 4I and. de.-V tachably locked in place.. Thel clamp members. 38 are provided with a screw driven slot 42? in their ends which are conveniently reached for attaching or disconnecting. the frame I2' from the fiue extensionI I3, or to adjust the frame IT- about the iiue extension t3'.

A platform 43 having an inwardly facing surface 44 disposed at an angle to the. inner f'ace of the pocket rear wall 23 is provided upon-said pocket rear wall to supportV the leaf spring stop member I6. Flanges 45 and 48 are-formed along; either side of the platform 43 to locate the spring member I and hold it against turning upon. its fastening member which member comprises alug 4.1. extending through the member I6 from the platform 43 and riveted' over upon the member I6.

The draft control device, improved by the' inclusion in its structure of the one-piece frame' member. I2 having the structural features above described, is especially eiicient in operation and` particularly practical to install` and adiust. The provision of the ller pieces 26, 21', 28, and 29` whereby the frame I2 may be accurately located upon the end ofthe flue extension I3 andr form cross braces` for the flanges 2| andV 22,. result in4 a strong frame structure which is practically free. from undesirable warping. The provision of the 4 clamping members 38 conveniently accessible from outside of the device, permits quick and efficient attachment or adjustment of the device into operative position.

While there has been shown and described herein one form in which the features and principles of this invention may be conveniently embodied in practice, it is to be understood that the same may be embodied in other specic forms without departing from the spirit and essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the claims rather than to the foregoing description to indicate the scope of the invention.

Having thus fully disclosed the invention, what is claimed as new and for which it is desired to secured Letters Patent, is:

1. In a draft controlling device, a frame member having a central opening, a damperv plate pivoted to said frame member within the opening therein, said frame member having a fiat rim portion, and an annular flange extending rearwardly and substantially at right angles' from the rim portion about the periphery of the central opening therein and being adapted to enter the open end of a iiue extension, lugs spacedV apart about the periphery of the ange, extending rearwardly fromr the rim portion, and being spaced laterally from the flange to allow the end of the flue extension to be disposedA therebetween, and means supported by said lugs to' clamp the flue extension against said flange.

2. In a draft controlling device, a frame member having a central opening, a damper plate pivoted to said frame member within the opening therein, said framemember having a fiat rim. portion and an annular flange extending rearwardly and substantially at right angles from the rim portion about the periphery of the central open ing therein and being adapted to enter the open end of a ue extension., lugs spaced: apa-rt about the periphery of the flange, extending rearwardly from the rim portion, and. being spaced. laterally from the flange to allow the end of the ueexe tension to be disposed therebetween, and threaded means Screw-threaded. through each of said. lugs to engage the nue extension end and clam-p it against said flange, a countersink in said flange in axial alignment with each of said threaded means, said threadedmeans having aV rounded end whereby the material of said flue extensionV where clampingly engaged thereby will be pressed. into the said co-untersinks to lock the frame member to the flueextension to prevent relative rotation thereof.

3. In a draft controlling device, a frame member having a central. opening, a damper plate pivoted to said frame member Iwithin the opening therein, said frame member havingV a hat -rim portion and an annular Aflange extendingv rearwardly and substantially at' right angles from the rim portion aboutthe periphery of the cen, tral opening therein and' beingl adapted to enter the open end of a flue extension, a second flange extending rearwardly about the periphery of said rim portion and. spaced. laterally from the rst mentioned flange, filler pieces. ex-V tending between said. flanges. and` being spaced; apart peripherally about said rim..portion,. the rear faces of said filler pieces being in the same plane to be engaged by the end. edge of the iiue extension to locate the frame rim parallel totheend edgev ofV the flue extension, lugs extending.,

rearwardly from at least one pair of flller pieces, said lugs being spaced laterally from the rst mentioned flange to receive the end of the flue extension therebetween, and means supported by said lugs to clamp the ue extension against said first mentioned flange. Y

4. In a draft controlling device, a frame member having a central opening, a damper plate pivoted to said frame member within the opening therein, said frame member having a flat rim portion and an annular flange extending rearwardly and substantially at right angles from the rim portion about the periphery of the central opening therein and being adapted to enter the open end of a flue extension, a second flange extending rearwardly about the periphery of said rim portion and spaced laterally from the first mentioned flange, filler pieces extending between said flanges and being spaced apart peripherally about said rim portion, the rear faces of said filler pieces being in the same plane to be engaged by the end edge of the flue extension to locate the frame rim parallel to the end edge of the flue extension, bearing members in diametrically opposite ller pieces for said damper plate, lugs extending rearwardly from at least one pair of ller pieces, said lugs being spaced laterally from the first mentioned flange to receive the end of the flue exten'- sion therebetween, and means supported by said lugs to clamp the flue extension against said first mentioned flange.

5. In a draft controlling device, a frame member having a central opening, a damper plate pivoted to said frame member to freely swing within the opening therein, said frame member pieces being in the same plane to be engaged by the end edge of the fiue extension to locate the frame rim parallel to the end edge of the ue extension, lugs extending rearwardly from at least one pair of filler pieces, said lugs being spaced laterally from the first mentioned flange to receive the end of the flue exten-sion therebetween, and threaded means screw-threaded through each of said lugs to engage the flue extension end and clamp it against said ange.

6. A frame for a draft controlling device, said frame having a flat forwardly facing circular rim portion, a first circular flange portion extending about the inner periphery of the rim portion and rearwardly at right angles therefrom to define a circular opening in the frame, a second circular ange portion extending about the outer periphery of the rim portion and rearwardly at right angles therefrom, said second flange being shorter in length than said rst flange, peripherally spaced apart filler pieces between said flanges with their rearwardly directed faces lying in the same plane, said first flange being adapted to be snugly received within the end of a flue pipe with the end edge of said pipe seated upon the rearwardly directed faces of said filler pieces, a lug extending rearwardly from diametrically opposite filler pieces with its inner face spaced outwardly from the first fiange to provide a space to receive the end of the flue pipe into which said first flange is inserted, and means carried by each lug to clamp the flue pipe against the first fiange.

HAL M. CUNNINGHAM.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,005,981 Morrow June 25, 1935 2,252,425 Crocker Aug. 12, 1941 2,289,196 Hutterer July '7, 1942 2,289,579 Klermund et al July 14, 1942 

